In a Time of Flight (ToF) based depth detecting camera or other diode emission based depth detection device, laser safety is a critical issue as is camera or device form factor. Various applications of such technology require varying light source power levels. The higher the power level required, the larger the diode's emission spot size must be to be considered Class 1 laser safe. A conventional depth camera 1, illustrated in FIG. 1, includes a laser light source 2 with a diffusing optic 3, and a light detector 4 with a receiving optic and filter 5. Laser safety is normally achieved by placing the diffusing optic 3 perpendicular to the emission path to increase the effective emission spot size 6 as seen by the viewer. The greater the distance D, i.e. the optic 3 is from the emission point of the light source 2, the larger the spot size 6 becomes. The higher the light source power, the larger the spot 6 needs to be and the further the diffusion optic 4 must be from the emission source to maintain Class 1 laser safety.
Unfortunately, in today's world of miniaturized electronic devices, having to increase the camera or diode emission based device's size in the direction D of a diode's natural emission path may not meet a particular application or device's form factor requirements.
In the camera 1, the depth D has to be minimized so that the camera 1 can be fit into very tight spaces in the bezels of various displays, e.g. TVs, Laptops, Tablets, Computer Monitors, and Cell Phones. Unfortunately, the dimension D is limited by the sensor receive optic 5 and the placement of the diffuser 3 based on a given optical power level to maintain Class 1 laser safety.
An object of the present invention is to overcome the shortcomings of the prior art by providing a low profile, small form factor depth camera that is capable of fitting into the bezels of a plurality of display devices.